Hi Otis, The type of spouts and bolts and the inter-connectivity between them is fixed. The number of (tasks) spouts and bolts is configurable but is also fixed for the lifetime of the topology. The topology should be re-deployed if it changes. However, the number of threads that work with these tasks are updateable by deactivating and re-activating the topology.
But, I did feel the need to dynamically add/remove bolts. In our environment, users configure policies which do specific aggregations over the data streams. Since these policies would be created/deleted by user, I thought it would be great to be able to dynamically alter the topology. Since that is not possible using Storm, we had to circumvent it by re-designing our streams. Regards, Srinath. On Fri, Apr 11, 2014 at 6:41 PM, Otis Gospodnetic < [email protected]> wrote: > Hi, > > I'm wondering how dynamic topologies are for most Storm users? > That is, do people tend to have topologies with a more or less fixed type > (and number?) of spouts & bolts? Or do people have topologies where > different types of spouts & bolts are regularly being added/removed? > > I'm asking because some of our SPM users who use it to monitor Storm > performance metrics are asking if they can see metrics for their spouts and > bolts. We didn't collect these metrics in the SPM based on the assumption > that topologies are very dynamic, meaning that spouts and bolts change a > lot and one would end up with a messy pile of different kinds of bolts & > spouts in the SPM UI, but..... > > .... now I'm wondering, is this actually a correct assumption? I now get > the feeling most people have 1 or more topologies with a more or less fixed > types (and even number?) of spouts & bolts. > > Could anyone please enlighten me? > > Thanks, > Otis > -- > Performance Monitoring * Log Analytics * Search Analytics > Solr & Elasticsearch Support * http://sematext.com/ > >
